In the majority of vehicles, the vehicle doors are fitted to the vehicle body such that they can rotate about the vertical axis or approximately about the vertical axis of the vehicle. When vehicle doors of this kind are opened, the vehicle doors pivot out into the area surrounding the side of the vehicle. In these vehicles, it may be particularly difficult for the vehicle occupant to enter and exit the vehicle, particularly when the vehicle is parked in a location at which objects, such as other vehicles or walls, trees, fences or the like, are located in the area immediately surrounding the side of the vehicle. The vehicle doors, which can rotate about the vertical axis of the vehicle, can in this case only be opened through a small door opening angle, so that the cleared area through which the vehicle occupant can leave the vehicle is very small.
In order to remedy this problem, the vehicle doors can also be fitted such that they cannot rotate about the vertical axis of the vehicle, but rather about the longitudinal axis. Doors of this kind are fitted in the roof of the vehicle and are often also called gull-wing doors. Furthermore, the doors can also be arranged such that they can pivot about the transverse axis or about a rotation axis of the vehicle which is inclined to a certain extent in relation to the transverse axis, as in the case of what are known as scissor doors. In the case of vehicle doors which are fitted in this way, the vehicle door, when open, is not moved or moved only to a slight extent into the area surrounding the side of the vehicle, but rather into an area above the vehicle, where, with the exception of garages with a low ceiling height, a sufficiently large amount of space without obstacles is generally available.
One disadvantage of these gull wing and scissor doors is that the vehicle design differs considerably from the conventional vehicle concepts, and therefore vehicle doors of this kind can be employed for large-scale production only to a limited extent. Consequently, vehicle doors of this kind are found only in a very small number of vehicles, in particular in high-end sports cars which are constructed in relatively small runs.
It would be desirable to make it easier for a vehicle occupant to enter and exit, even if the vehicle door is fitted to the vehicle such that it can rotate about the vertical axis, without further changes to the vehicle design being required for this purpose.